Biodegradable polymers based on renewable resources.: IX.: Synthesis and degradation behavior of polycarbonates based on 1,4:3,6-dianhydrohexitols and tartaric acid derivatives with pendant functional groups
Biodegradable polymers based on renewable resources.: IX.: Synthesis and degradation behavior of polycarbonates based on 1,4:3,6-dianhydrohexitols and tartaric acid derivatives with pendant functional groups
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DOI：
10.1002/pola.20830
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发表时间：
2005-09-01
影响因子：
--
通讯作者：
Okada, M
中科院分区：
文献类型：
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作者：
Yokoe, M;Aoi, K;Okada, M
以1，4：3，6-二脱水己糖醇和L-酒石酸为原料合成了新型侧基聚碳酸酯。1，4：3，6-二脱水-双-O-（对硝基苯氧基羰基）己糖醇与2，3-二-O-甲基-L-苏糖醇或2，3-O-异亚丙基-L-苏糖醇的溶液缩聚分别得到具有侧基甲氧基或异亚丙基的聚碳酸酯，其数均分子量（M-n）值高达3.6（1）× 10（4）。随后的异亚丙基的酸催化脱保护得到具有沿聚合物链沿着规则分布的侧羟基的明确限定的聚碳酸酯。差示扫描量热法（DSC）表明，所有的聚碳酸酯都是无定形的，玻璃化转变温度为57至98 ℃。通过在37 ℃下在磷酸盐缓冲溶液中的水解试验和通过在25 ℃下在活性污泥中的生化需氧量（BOD）测量来评估聚碳酸酯的降解性。在两个测试中，具有侧羟基的聚碳酸酯比具有侧甲氧基和异亚丙基的聚碳酸酯降解得快得多。值得注意的是，具有侧羟基的聚碳酸酯的降解非常快。它们在磷酸盐缓冲溶液中仅在150 min内完全降解，28 d后在活性污泥中的BOD-生物降解率达到近70%。根据聚碳酸酯的化学和物理性质讨论了其降解行为。(c)2005 Wiley Periodicals，Inc.
Novel polycarbonates, with pendant functional groups, based on 1,4:3,6-dianhydrohexitols and L-tartaric acid derivatives were synthesized. Solution polycondensations of 1,4:3,6-dianhydro-bis-O-(p-nitrophenoxycarbonyl)hexitols and 2,3-di-O-methyl-L-threitol or 2,3-O-isopropylidene-L-threitol afforded polycarbonates having pendant methoxy or isopropylidene groups, respectively, with number average molecular weight (M-n) values up to 3.6(1) x 10(4). Subsequent acid-catalyzed deprotection of isopropylidene groups gave well-defined polycarbonates having pendant hydroxyl groups regularly distributed along the polymer chain. Differential scanning calorimetry (DSC) demonstrated that all the polycarbonates were amorphous with glass transition temperatures ranging from 57 to 98 degrees C. Degradability of the polycarbonates was assessed by hydrolysis test in phosphate buffer solution at 37 degrees C and by biochemical oxygen demand (BOD) measurements in an activated sludge at 25 degrees C. In both tests, the polycarbonates with pendant hydroxyl groups were degraded much faster than the polycarbonates with pendant methoxy and isopropylidene groups. It is noteworthy that degradation of the polycarbonates with pendant hydroxyl groups was remarkably fast. They were completely degraded within only 150 min in a phosphate buffer solution and their BOD-biodegradability reached nearly 70% in an activated sludge after 28 days. The degradation behavior of the polycarbonates is discussed in terms of their chemical and physical properties. (c) 2005 Wiley Periodicals, Inc.